Heated drum compactor machine and method

ABSTRACT

A compactor machine includes a frame and at least one compactor drum mounted to the frame. The at least one compactor drum has an outer surface configured for compacting asphalt. A heating system is configured to heat the outer surface and includes a control device configured to control an output of the at least one heating element to the outer surface. A related method for providing a heated drum for a compactor includes mounting at least one heating element and a control device for the at least one heating element to a compactor machine, and coupling the control device with the at least one heating element to enable controlling an output thereof to an outer surface of the compactor drum.

TECHNICAL FIELD

The present disclosure relates generally to strategies for inhibiting adhering of asphalt to components of a compactor machine, and relates more particularly to a heated drum compactor machine and method for providing a heated drum.

BACKGROUND

A wide variety of machines for paving and compacting asphalt have been used for decades. The term “asphalt” is used broadly herein in reference to the class of paving materials consisting of aggregate mixed with one or more viscous materials such as petroleum-derived asphalt, other definitions for “asphalt” notwithstanding. A conventional approach for paving a surface such as a road or parking lot is to distribute hot paving material onto a prepared bed with a paving machine, then follow the paving machine with one or more compactor machines to compact the material to a desired density and obtain an acceptable surface finish. Most commonly, the compacting process is performed with double drum compactors, having a front drum and a back drum, which serve to propel the machine and compact the asphalt to a suitable state via the weight of the compactor, often in cooperation with drum vibrating apparatuses. Completing compaction can often require multiple passes across the asphalt mat with a compactor machine.

Sticky, viscous properties of hot asphalt can cause it to adhere to paving and compacting equipment where relatively cool machine components come into contact with the asphalt. This tendency for hot asphalt to stick to machine surfaces is generally a function of the heat transfer out of the asphalt. The asphalt congeals and increases in viscosity where it is cooled by contact with machine surfaces. The greater a difference in temperature between the asphalt and machine surfaces, the greater the tendency for asphalt to stick. Recognizing this phenomenon, engineers have developed several ways to address asphalt sticking problems over the years.

As asphalt is laid down by a paver, a component of the paver known as a screed is typically used to prepare the asphalt for compacting. Screeds commonly consist of a metallic implement having a surface which slides across a pile of asphalt deposited on a work surface to level and slightly compact the asphalt in anticipation of further working by a compactor. The efficacy of the screed and ultimately quality of the paving job may be affected where asphalt adheres to the screed instead of smoothly slipping past the screed surfaces. In other words, asphalt stuck to the screed can affect the ability of the screed to provide an asphalt mat suitable for finishing with a compactor machine. Irregularities in the asphalt mat laid down in advance of the compactor machine(s) can result in unevenness in the later compacted surface. To address this issue, a screed heater may be employed to heat the back side of the flat plate which slides across the pile of asphalt. Hot fluid circuits, gaseous or liquid fueled burners and electric heaters are used for this purpose. The temperature of the screed surface which contacts asphalt may thereby be increased up to a point at which heat transfer from the asphalt to the screed is reduced or negligible. Accordingly, asphalt has less of a tendency to congeal on the heated screed surface and compromise the planarity and/or uniformity of a finished asphalt mat.

After deposition and working by a paver, the asphalt cools somewhat prior to being compacted. However, the asphalt is still typically hot enough to have sticking problems with components of compactor machines following the paver. Certain compactor designs use tires or belts to compact asphalt, and some of these machines utilize heaters to heat the tires/belts to inhibit adhering of asphalt. The most prevalent known strategy by far, however, is to spray water, detergent or even fuel onto a compacting unit's surface to prevent asphalt from sticking. Such machines also often use a scraper to remove any asphalt that does happen to stick to the drum. While such approaches have a long history of success, there are various reasons why alternatives may be desirable in some situations.

Using the water spray or detergent spray approach requires an extra on-board fluid tank, whereas fuel spray strategies obviously consume excess fuel. Moreover, operating weight of a compactor machine can change due to the consumption of a large volume of fluid carried on board. As an alternative, smaller volumes of water, etc. having less of a proportionate effect on the overall weight of the machine may be used; however, this strategy can require relatively frequent stops to refill the tank and still generally requires a water truck and extra operator on-site.

Further, in conventional fluid spray systems portions of the drum are typically made visible to an operator to allow him or her to inspect the drum for asphalt that does happen to stick. Many drum compactors also utilize noisy vibratory apparatuses to enhance compacting of the asphalt. Noise issues are an increasing problem as some jurisdictions have enacted, or are expected to enact, heightened noise regulations for many types of construction equipment. Exposed drums can permit excessive noise to escape and/or require that such vibratory devices be operated at lower amplitudes than what would otherwise be considered ideal. It will thus be readily apparent that improved strategies for reducing asphalt sticking issues in drum compactors, as well as noise suppression, would be welcomed by the industry.

The present disclosure is directed to one or more of the problems or shortcomings set forth above.

SUMMARY OF THE DISCLOSURE

In one aspect, the present disclosure provides a compactor machine having a frame, a front compacting element and a back compacting element mounted to the frame. At least one of the compacting elements includes a compactor drum having an outer surface configured for compacting asphalt. The compactor machine further includes a heating system configured to heat the outer surface, the heating system having at least one heating element and a control device configured to control an output of the at least one heating element to the outer surface.

In another aspect, the present disclosure provides a method for providing a heated compactor drum for a compactor machine. The method includes mounting at least one heating element to a compactor machine having a front compacting element and a back compacting element, at least one of the compacting elements comprising a compactor drum. The method further includes coupling a control device with the at least one heating element to enable controlling an output of the at least one heating element to an outer surface of the compactor drum.

In still another aspect, the present disclosure provides a compactor machine having a frame and at least one compactor drum mounted to the frame, the at least one compactor drum having an outer surface configured for compacting asphalt. The compactor machine further includes a heating system configured to heat the outer surface, the heating system having at least one heating element and a control device configured to control an output of the at least one heating element to the outer surface. The compactor machine further includes an electrical power source mounted on the compactor machine, the at least one heating element including at least one electrically powered heating element coupled with the electrical power source.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side diagrammatic view of a compactor machine according to one embodiment;

FIG. 2 is a schematic illustration of a heating system for a compactor drum according to one embodiment;

FIG. 3 is a side diagrammatic view of a heated compactor drum system according to one embodiment; and

FIG. 4 is a perspective view of a heated compactor drum system according to another embodiment.

DETAILED DESCRIPTION

Referring to FIG. 1, there is shown a compactor machine 10 according to one embodiment of the present disclosure. Compactor machine 10 is illustrated as a self-propelled double drum compactor having a front drum 16 and a back drum 14, each of which may be housed within an enclosure 17 and 15, respectively. For reasons which will be apparent from the following description, enclosures 15 and 17 may include an insulating material such as a layer of fibrous, foam or another insulating material to inhibit heat and/or sound escaping from within the respective enclosures 15 and 17. Compactor machine 10 may include an operator station 18, an engine 20 and a generator 22 coupled with engine 20. Generator 22 may serve as an electrical power source for various onboard systems and components, as further discussed herein. Engine 20 may comprise an internal combustion engine such as a diesel engine, configured to drive generator 22. In one embodiment, compactor machine 10 could comprise an electric drive machine having electric motor(s) 21 configured to power one or both of drums 14 and 16 and electrically powered steering actuator(s) 23, all powered via generator 22.

It should be appreciated, however, that compactor machine 10 is illustrative only as depicted in FIG. 1 and a wide variety of compactor machines might be designed and/or controlled in accordance with the present disclosure. For example, rather than a double drum compactor machine, compactor 10 might include only a single drum and some other type of compacting element. For instance, the front “compacting element” might be a drum, and the back compacting element could be a belted or pneumatic compacting element. Moreover, compactor machine 10 might comprise a tow-behind or pushed compacting apparatus. Operator station 18 might also be dispensed with in versions where compactor machine 10 is operated in an autonomous fashion and a remote control or self guidance system used. In any of the various contemplated embodiments, a heating system 29 will be included which is configured to heat at least one compacting drum of the machine. Heating system 29 may include a control device 30 configured to control heating system 29 to inhibit asphalt sticking to drums 14 and 16, in a manner further described herein.

Each of compactor drums 14 and 16 may include an outer surface, shown via reference numeral 34 on drum 16, configured for compacting asphalt. Outer surface 34 may consist of a cylindrical, smooth metallic drum surface comprising the exterior of a shell of drum 16. As compactor machine 10 is passed across an asphalt mat to compact it, outer surface 34, and the corresponding outer surface of drum 14, will roll against an asphalt mat laid by a paver. As a result, the asphalt of the mat will increase in density and develop a relatively smooth surface finish. As mentioned above, heating system 29 may be used to heat drum 16, in particular outer surface 34, prior to and/or during the compacting process.

Control device 30 may be used to control heating system 29 during increasing the temperature of outer surface 34 from an ambient temperature to a higher temperature sufficient to inhibit adhering of asphalt thereto. Control device 30 may also be used in controlling a temperature of outer surface 34 once heated to keep outer surface 34 at a desired temperature or within a desired temperature range. It has been discovered that where a drum outer surface has a temperature within a range of about 20° F. of an asphalt temperature, asphalt will not typically substantially adhere to the drum outer surface. Depending upon the particular project, different types of asphalt mixtures having different properties may be laid and subsequently compacted at different optimal temperatures. Thus, the actual temperature or temperature range at which drum 16 is maintained may depend upon the chosen asphalt type. Moreover, control device 30 might include a plurality of temperature set points corresponding to different types of asphalt. In still further embodiments, control device 30 might be programmable with different user-entered temperature settings. While much of the present description emphasizes apparatus and method associated with a single drum, it should be appreciated that the present description is similarly applicable to design and heating system control for a second drum, such as drum 14. In most embodiments, where double drum compactors such as compactor 10 are used each of the drums may be heated and temperature controlled in the manner described herein. Control device 30 might thus be configured to control heating of each of drums 14 and 16 via one or more heating systems such as heating system 29.

Compactor machine 10 of FIG. 1 illustrates one exemplary heating system 29, but as will be apparent from the following description, a wide variety of heating systems and temperature control strategies are contemplated within the context of the present disclosure. In the embodiment of FIG. 1, an electrical output from generator 22 may be routed via control device 30 to a plurality of heating elements 36 positioned radially about an axis A of drum 16 and spaced from outer surface 34. It will be noted that the average position of heating elements 36 may be relatively closer to outer surface 34 than to axis A. Each of heating elements 36 may thus comprise an electrically powered heating element, and in certain embodiments may comprise radiant heating elements, for example infrared heaters. In other embodiments, however, rather than radiant electrically powered heaters, some other heating elements might be used such as contact heating elements which actually contact outer surface 34. Combustible gas radiant heaters might also be used. A variety of gas powered heaters, for instance having tubes that glow and radiate heat energy when hot gas is passed through them could be substituted for heating elements 36. In still other embodiments, a blower coupled with an electric heater or a furnace such as a diesel or propane furnace could be used to provide heated gas for heating outer surface 34. In the illustrated heating system 29 a plurality of reflective elements 38 may be positioned radially about axis A, and associated one with each of heating elements 36, to assist in reflecting infrared radiation toward outer surface 34. In other embodiments, a single heating element such as a reflective coating or panel might be disposed within enclosure 17 to reflect heat energy toward outer surface 34. The use of one or more reflective elements 38 is contemplated to be useful not only for reflecting heat energy radiated by heating elements 36 toward outer surface 34, but also for reflecting heat energy radiated from outer surface 34 back toward outer surface 34.

Heating system 29 may be thermostatically controlled, hence, control device 30 may comprise a thermostatic control device. To this end, a temperature sensor 32 may be positioned within enclosure 17 and oriented such that a temperature of outer surface 34 may be sensed as surface 34 is rotated past temperature sensor 32. Temperature sensor 32 may comprise a non-contact temperature sensor spaced from outer surface 34 which operates by directly sensing a temperature of outer surface 34, for instance by sensing infrared radiation. Alternatively, temperature sensor 32 might actually contact outer surface 34, or it might be used to indirectly determine temperature of outer surface 34, for example by sensing a temperature of air within enclosure 17. In still other embodiments, temperature sensor 32 or another temperature sensor might sense an asphalt temperature and output signals indicative of asphalt temperature for use by control device 30 in controlling a temperature of outer surface 34.

Turning to FIG. 2, there is shown a schematic illustration of heating system 29 and related components. Control device 30 may include a thermostat 40 coupled with temperature sensor 32, and also coupled with a relay 42. Relay 42 may be configured to connect generator 22 with heating elements 36 via first and second electrical lines 46 and 48. Relay 42 may further include a first switch and a second switch, each identified with reference numeral 44, and have at least two states, at least one of which is a state which allows electrical power to flow from generator 22 to heating elements 36. Relay 42 might also include a plurality of states, each corresponding to a different degree of power flow between generator 22 and heating elements 36, resulting in different levels of heat output of heating elements 36 to outer surface 34. First and second actuators 50 may be coupled one with each of switches 44, and configured to control a position of switches 44 responsive to an output of thermostat 40. Those skilled in the art will appreciate that there are a wide variety of ways in which control device 30, and the overall heating system 29, might be configured for thermostatic control. Operator controls for heating system 29 might also be provided. It should still further be appreciated that embodiments are also contemplated wherein rather than a thermostatic control device, radiant heater output or some other form of heat output such as blower rate to outer surface 34 is controlled without a thermostat. For example, a gas burner might be used as a heater for outer surface 34 which simply burns propane gas at a rate considered appropriate for maintaining a temperature of outer surface 34 within a desired range, or raise a temperature of outer surface 34 to a temperature sufficient for inhibiting adhering of asphalt thereto.

Turning now to FIG. 3, there is shown another embodiment wherein a drum 116 is heated internally rather than via externally positioned heating elements as in the FIG. 1 embodiment. Drum 116 may include a rotatable electrical connector 170 having an outer portion 174 and an inner portion 172. One of inner and outer portions 174 and 172 may be configured to rotate with compactor drum 116, whereas the other of portions 172 and 174 may be fixed relative to a frame of the associated compactor machine. Electrical lines 46 and 48 may extend from a control device 30 to connector 170 such that electrical power may be supplied via an interface of portions 172 and 174 (not shown) to electrically powered components inside drum 116. Examples of rotatable electrical connector 170 include “slip rings” and commutators, although other devices known in the art may also be used. From connector 170, additional electrical lines 146 and 148 may extend internally of drum 116 to a plurality of heating elements 136 positioned radially about an inside of compactor drum 116. Heating elements 136 may thus comprise electrically powered heating elements, which might be radiant or other types of electrically powered heating elements. In other embodiments, a fuel line might connect from a fuel tank to inside drum 116 for supplying fuel to one or more combustion heaters. Heating elements 136 may be thermally coupled with outer surface 134 of drum 116 via a suitable thermal grease 180. Inputs from a temperature sensor 32 may also enable control device 30 to thermostatically control heating elements 136. Drum 116, as well as any of the other drums described herein, may also include a vibratory apparatus 160, for example, having any of a variety of designs familiar to those of skill in the art. Vibratory apparatus 160 may be hydraulically powered, electrically powered, etc.

Referring to FIG. 4, there is shown a compactor drum 216 according to yet another embodiment of the present disclosure. Compactor drum 216 may be heated via an induction heating system 229 configured to heat an outer surface 234 of drum 216 to inhibit adhering of asphalt thereto by inducing electrical currents therein. Heating system 229 may include a control device 230 coupled with a temperature sensor 232 and an electrical power source 222. Heating system 229 may also be thermostatically controlled, and could include a thermostat as one component of control device 230 (not shown). Electrical power source 222 may comprise a high frequency power source coupled with at least one induction coil 290 of an electrically conductive material such as copper or the like which is configured to induce electrical currents in drum 216 to heat outer surface 234 via induction heating. Electrical power source 222 may be driven directly or indirectly via an engine of a compactor machine of which drum 216 is a part. Induction coil 290 may also be mounted within an enclosure (not shown) about drum 216 similar to enclosures 15 and 17 shown in FIG. 1. Coil 290 may include an inlet 292 and an outlet 294 for passing cooling fluid therethrough in a manner commonly employed in induction heating systems. It may be noted from the FIG. 4 illustration that drum 216 includes a diameter D and a width W which is greater than its diameter D, features common to all of the drum designs described herein.

INDUSTRIAL APPLICABILITY

Referring to the drawings generally, similar to conventional paving practice, compactor machine 10, and possibly a plurality of such machines, may follow a paver distributing asphalt onto a work surface such as a prepared road bed or the like. Prior to beginning to compact asphalt, it may be desirable to preheat compactor drums 14 and 16. The following description focuses primarily on drum 16, however, it should be understood to refer also to heating/controlling temperature of drum 14, as well as the other embodiments described herein, except as otherwise noted. Preheating may take place prior to driving compactor 10 onto asphalt, while loaded on a transfer machine, etc. In one preheating strategy, engine 20 may be started and used to power generator 22 such that electrical power is available to heating elements 36. Once control device 30 is activated, which may take place upon turning an ignition key for compactor 10, thermostat 40 will receive inputs from temperature sensor 32 corresponding to a temperature of outer surface 34 of drum 16. Thermostat 40 will typically be configured to turn relay 42 on, if it is not already on, when signals from temperature sensor 32 indicate that outer surface 34 is below a desired temperature or temperature range considered appropriate for inhibiting sticking of asphalt.

With power available from generator 22, heating elements 36 may begin to radiate heat energy toward outer surface 34, reflective elements 38 reflecting heat energy that might otherwise be wasted back toward outer surface 34. In the embodiments of FIGS. 3 and 4, preheating and temperature control of the respective drums may take place in a similar manner, albeit without reflecting heat energy with reflective elements 38. It may be desirable to achieve relatively uniform heating of outer surface 34 as rapidly as possible to avoid undue delay in getting compactor 10 onto the asphalt. To bring outer surface 34 up to temperature as efficiently as possible, compactor 10 may be driven or drum 16 otherwise rotated such that outer surface 34 is exposed generally uniformly to a heat output of heating elements 36, although in some instances a thermal conductivity of drum 16 may be sufficient to bring outer surface 34 to a uniform temperature within a reasonable time without rotating drum 16. Temperature sensor 32 may be coupled with a machine controller (not shown) on board compactor 10 which is configured to indicate to an operator that compactor 10 is ready to being work, or some other means of determining outer surface 34 is sufficiently heated might be used.

Once compactor machine is ready to begin compacting asphalt, it will typically be driven onto the asphalt mat. During operation, drums 14 and 16 will tend to be heated via contact with the hot asphalt, reducing a need for heating via heating elements 36. Drums 14 and 16 will tend to lose a certain amount of heat to ambient, even with enclosures 15 and 17 and, hence, supplemental heating with heating system 29 may often take place. As described above, temperature sensor 32 may continuously or intermittently output signals indicative of a temperature of outer surface 34. Control device 30 may control supplying of electrical power to heating elements 36 in response to an output of temperature sensor 32, thereby maintaining a temperature of outer surface 34 at or close to a desired temperature considered appropriate for inhibiting adhering of asphalt. The embodiments shown in FIGS. 2 and 3 operate in a manner similar to that described with regard to the FIG. 1 embodiment, albeit through the use of internal heating elements with drum 116 and the use of induction heating in the system associated with drum 216.

The present disclosure thus provides an altogether new strategy for inhibiting adhering of asphalt to compactor drums. Earlier approaches to this problem in drum compactors utilized bulky, heavy, unwieldy and sometimes ineffective means for inhibiting sticking and removing asphalt. While it has been known for some time to use electric heaters in the context of pneumatic compactor machines, such strategies are not applicable to the differing materials, properties and use of drum compactors, and typically require an operator's best guess as to how long to heat the tires, how often to apply supplemental heat, and when the tires are sufficiently heated. This can result in a risk of damaged tires, wasted energy and compromised compaction quality, as well as requiring operator monitoring and activity. The present disclosure offers a far more elegant and effective approach in the context of drum compactors in that a control strategy useful for both preheating drums and maintaining drum temperature is possible rather than simply relying on an operator's best guess.

The present strategy provides the additional advantage over earlier strategies in that an operator does not need to monitor the compactor drum surfaces to assure that asphalt does not stick. Since asphalt does not stick to the drum surfaces at all or only negligibly with the present approach, the overall quality of the finished paved surface can be improved over earlier paving strategies without requiring close monitoring to ensure nothing is going wrong. The foregoing features together also make a truly autonomous compactor machine much more practicable than with earlier designs, as all or substantially all of the machine systems may be electrically powered and do not require operator interaction. It is contemplated that engine 20 may comprise a diesel engine configured to run continuously at an optimal speed, providing power for motor(s) 21, steering actuator(s) 23 and heating system 29. Vibratory apparatus 160 may also be electrically powered. Remote control of one or more machines, or automated path planning by a computer, may be used to substantially improve performance and efficiency of a paving operation.

Yet another advantage afforded by the present disclosure is the increased heat retention and noise suppression made possible by substantially enclosing the drums, as shown in FIG. 1. Certain jurisdictions have recently enacted regulations as to the amount or intensity of noise associated with certain construction machines. In the example embodiment of FIG. 1, the use of enclosures 15 and 17 will allow certain machines to be operated in environments and via operating methods previously unavailable. For instance, relatively high amplitude vibration may be most appropriate for certain compacting jobs, but undesirable due to excessive noise levels. Thus, enclosures 15 and 17 will not only reduce absolute noise levels, but may also make higher vibration amplitudes practicable and provide improved heat retention of the drums.

The present description is for illustrative purposes only, and should not be construed to narrow the breadth of the present disclosure in any way. Thus, those skilled in the art will appreciate that various modification might be made to the presently disclosed embodiments without departing from the full and fair scope of the present disclosure. Other aspects, features and advantages will be apparent upon an examination of the attached drawings and appended claims. 

1. A compactor machine comprising: a frame; a front compacting element and a back compacting element mounted to said frame, at least one of said compacting elements comprising a compactor drum having an outer surface configured for compacting asphalt; a machine propulsion device configured to power at least one of the front compacting element and the back compacting element: and a heating and preheating system which is separate from the machine propulsion device and configured to heat said outer surface when said compactor drum is rotating and further configured to preheat said outer surface when said compactor drum is not rotating; said heating and preheating system having at least one heating element and a control device configured to control an output of said at least one heating element to said outer surface.
 2. The compactor machine of claim 1 wherein said control device comprises a thermostatic control device.
 3. The compactor machine of claim 2 wherein said control device further comprises a temperature sensor configured to sense a temperature of said outer surface and a thermostat coupled with said temperature sensor which is configured to adjust a heat output of said at least one heating element responsive to an output of said temperature sensor.
 4. The compactor machine of claim 3 wherein said temperature sensor comprises a non-contact temperature sensor.
 5. The compactor machine of claim 4 wherein said compactor drum comprises an axis of rotation, a width aligned with said axis of rotation and a diameter perpendicular said axis of rotation which is less than said width, and wherein said at least one heating element comprises a plurality of heating elements positioned at a first average distance from said axis of rotation and at a second average distance from said outer surface which is less than said first average distance.
 6. The compactor machine of claim 1 further comprising an electrical power source, wherein said at least one heating element comprises at least one electrically powered heating element coupled with said electrical power source.
 7. The compactor machine of claim 6 wherein said control device further comprises a temperature sensor, a thermostat coupled with said temperature sensor and a relay having at least two different states, wherein said relay is configured to connect said electrical power source with said at least one electrically powered heating element, and wherein said thermostat is configured to switch said relay between said at least two different states responsive to an output of said temperature sensor.
 8. The compactor machine of claim 1 wherein said at least one heating element comprises at least one radiant heater.
 9. The compactor machine of claim 8 wherein said compacting elements comprise a front compactor drum and a back compactor drum, said compactor machine further comprising: a first enclosure and a second enclosure mounted to said frame and extending about said front and back compactor drums, respectively, said at least one radiant heater including a plurality of radiant heaters mounted within each of said enclosures; and at least one reflective element mounted within each of said enclosures and configured to reflect radiation from the radiant heaters toward the outer surface of the corresponding compactor drum.
 10. The compactor machine of claim 1 wherein said at least one heating element comprises at least one electrically powered heating element disposed within said compactor drum, said heating system further comprising an electrical power source and a rotatable electrical connector coupled with said compactor drum which is configured to supply electrical power from said electrical power source to said at least one electrically powered heating element.
 11. The compactor machine of claim 1 wherein said compacting elements comprise a front compactor drum and a back compactor drum, said compactor machine further comprising: a first enclosure and a second enclosure extending about said front and back compactor drums, respectively; wherein said at least one heating element includes at least one induction coil associated with each one of said compactor drums and configured to heat the outer surface of the corresponding drum.
 12. A method of providing for heating and preheating of a compactor drum for a compactor machine comprising the steps of: mounting a heating and preheating system including at least one heating element having a plurality of heat output states to a compactor machine having a machine propulsion device separate from the at least one heating element, the compactor machine further including a front compacting element and a back compacting element, at least one of the compacting elements comprising a compactor drum; coupling a control device with the at least one heating element to enable controlling an output of the at least one heating element to an outer surface of the compactor drum; coupling a temperature sensor with the control device, the temperature sensor being configured to generate outputs corresponding to a temperature of the outer surface of the compactor drum; and switching the control device between a first control device state corresponding with a first heat output state of the at least one heating element and a second control device state corresponding to a second, different heat output state of the at least one heating element, responsive to inputs from the temperature sensor.
 13. The method of claim 12 wherein the step of mounting at least one heating element to the compactor machine further comprises mounting a plurality of electrically powered heating elements radially about the compactor drum, the method further comprising a step of coupling the electrically powered heating elements with an electrical power source of the compactor machine.
 14. The method of claim 13 wherein the step of mounting at least one heating element to the compactor machine comprises mounting a plurality of radiant heating elements at locations spaced from the outer surface of the compactor drum.
 15. The method of claim 14 further comprising the steps of mounting the temperature sensor to the compactor machine at a location spaced from the outer surface of the compactor drum, and connecting a thermostat of the control device with the temperature sensor.
 16. The method of claim 15 wherein the step of connecting a thermostat of the control device with the temperature sensor further comprises enabling receipt of inputs from the temperature sensor to control a heat output of the at least one heating element to the outer surface of the compactor drum during rotating the compactor drum past the temperature sensor.
 17. The method of claim 12 wherein the step of mounting at least one heating element to the compactor machine further comprises mounting a plurality of electrically powered radiant heating elements within an enclosure extending about the compactor drum, the method further comprising a step of mounting at least one reflective element within the enclosure to reflect radiant heat energy toward the outer surface of the compactor drum.
 18. A compactor machine comprising: a frame; at least one compactor drum mounted to said frame, said at least one compactor drum having an outer surface configured for compacting asphalt; a machine propulsion device configured to power said at least one compactor drum; a heating and preheating system which is separate from the machine propulsion device and configured to heat said outer surface when said compactor drum is rotating and further configured to preheat said outer surface when said compactor drum is not rotating; said heating and preheating system having at least one heating element and a control device configured to control an output of said at least one heating element to said outer surface; and an electrical power source mounted on said compactor machine, said at least one heating element comprising at least one electrically powered heating element coupled with said electrical power source.
 19. The compactor machine of claim 18 wherein said at least one compactor drum comprises a front compactor drum and a back compactor drum, said compactor machine further comprising: a first enclosure and a second enclosure mounted to said frame and extending about said front and back compactor drums, respectively, said at least one heating element including a plurality of radiant heaters mounted within each of said enclosures; and at least one reflective element mounted within each of said enclosures and configured to reflect radiation from the radiant heaters toward the outer surface of the corresponding compactor drum.
 20. A method of preparing a compactor machine for compacting asphalt comprising the steps of: mounting a heating and preheating system including at least one heating element having a plurality of heat output states to a compactor machine having a machine propulsion device which is separate from the at least one heating element, the compactor machine further including a front compacting element and a back compacting element, at least one of the compacting elements comprising a compactor drum; coupling a control device with the at least one heating element, the control device including a plurality of control device states corresponding to the plurality of heat output states; and preheating the outer surface of the compactor drum via the at least one heating element when the compactor drum is not rotating, including controlling a heat output of the at least one heating element via the control device. 